Co-occurrence of in-stream nitrogen fixation and denitrification across a nitrogen gradient in a western U.S. watershed, 2015 - 2016

This data was collected as part of the NSF CAREER Grant DEB 14-51919 to Amy Marcarelli to evaluate if nitrogen fixation and denitrification co-occur in streams across a gradient of nitrate concentrations. This data was collected during summer 2015 and 2016 in the Portneuf River watershed near Pocatello, ID. In summer 2015, rates of nitrogen fixation were only measured on rock substrate and denitrification only on sediment substrate. In summer 2016, both process rates were measured on both rock and sediment substrate to more accurately capture variation in rates.本数据集依托美国国家科学基金会（National Science Foundation, NSF）编号为DEB 14-51919的CAREER奖项目采集，资助人为Amy Marcarelli，旨在评估硝酸盐浓度梯度下的溪流中，固氮作用（nitrogen fixation）与反硝化作用（denitrification）是否共存。数据采集于2015年与2016年夏季，采集地点为爱达荷州波卡特洛市附近的波蒂厄河（Portneuf River）流域。2015年夏季仅在岩石基质（substrate）上测定固氮速率，仅在沉积物基质上测定反硝化速率；2016年夏季则同时在岩石与沉积物基质上测定两种过程的速率，以更精准地捕捉速率的变异特征。